My wife is a tech nerd who does well, I own some websites which do well, we don't have kids, we are Canadian so we never had any medical or student debt at all, and we live a slightly different lifestyle than most where we're both 100% independent so we do and spend what we want without asking the other. Not that this helps you at all though because your circumstance is totally different but I'd say this much. I met a young couple in their 20's playing pinball at a location who were in the more typical American circumstance of student debt, medical bills, etc and what they were doing is each putting aside an approved amount every week into a pinball fund to eventually buy their first machine. It's not a lot of money and it will take time, but they were determined to get there!
So generally speaking for those in a circumstance where money is tight and/or your spouse has to approve purchases then my suggestion would be to create a pinball fund that you tell your spouse about and you contribute an approved amount to it every week. It will take time but at least that way once you have enough saved up then you can buy your machine without grief. After that I would stick to trading games. Play the hell out of that game, enjoy it, then take time to find the right trade deal to get another game. That way with little to no money involved you won't get any spousal grief since it's a game for game swap, and no extra space gets taken. It's that 1st game that is the tricky one to get this way but once you got it then you are on your way! For repairs and game tweaks just hit Pinside and Youtube for help, I knew nothing about fixing pins when I got my first one but I learned everything I needed from those two resources, they are both goldmines of info.